Storing hazardous waste material underground may have significant risks. One risk may be that the hazardous waste material, or byproducts of the hazardous waste material, may enter into a source of human-consumable water. Some subterranean formations allow mobile water; that is the movement of water stored in the formation to a location in which human-consumable water is located. Therefore, any hazardous waste material stored underground must be kept from a source of mobile water.